1. Field of the Invention
The invention relates to a pressure vessel, more particularly to a pressure vessel having a structure for preventing deformation of a lining container therein.
2. Description of the Related Art
Hydro-pneumatic pressure vessels are widely used in industrial and residential piping systems. For example, hydro-pneumatic pressure vessels are used for stabilizing water pressure and absorbing water hammers in hydraulic piping systems, absorbing thermal expansion in closed hot water systems and storing water in reverse osmosis systems.
As shown in FIG. 1, a pressure vessel disclosed in Taiwanese Patent Publication No. 533,905 includes an outer container 1, a plastic lining container 2 sleeved by the outer container 1, and an elastic diaphragm 4 having an end portion that is clamped between an end portion of the lining container 2 and a pressing member 3. The diaphragm 4 divides an inner space of the outer container 1 into an air chamber 6 and a water chamber 5 that corresponds to the lining container 2. Despite being widely used, the above-mentioned pressure vessel suffers from a drawback: coupling between the outer container 1 and the lining container 2 is not air-tight, such that high-pressure air in the air chamber 6 may leak into a space between the outer container 1 and the lining container 2. Once the pressure in the water chamber 5 drops suddenly to be much smaller than the pressure in the space between the outer container 1 and the lining container 2, the lining container 2 may deform toward the water chamber 5. The deformation of the lining container 2 may be irreversible and may have an adverse effect on performance of the pressure vessel.